To help visualize the process, the video above demonstrates the growth of human iPS cells over several weeks, as they spontaneously form four concentric zones. Each of these zones exhibits the characteristics of a different part of the eye, including the cornea, the lens, and the retina.
During the trial phase of their experiment, the Japanese team managed to culture and grow sheaths of rabbit corneas that actually enabled blind animals to see again. In tests, lab-grown corneas were given to rabbits born without this crucial part of the eye, resulting in restored vision. And while humans have yet to experience the potential benefits of this breakthrough, our species is next.
“We are now in the position to initiate first in-human clinical trials of anterior eye transplantation to restore visual function,” Nishida wrote in the team’s findings, published in Nature. The biologist is of the opinion that within three years, humans may be able to overcome blindness by way of stem-cell-grown corneas (and perhaps even other eye components).
“This research shows that various types of human stem cells are able to take on the characteristics of the cornea, lens, and retina,” said Professor Andrew Quantock of Cardiff University, who was also involved in the study. “Importantly, it demonstrates that one cell type — the corneal epithelium — could be further grown in the lab and then transplanted onto a rabbit’s eye where it was functional, achieving recovered vision.”
Incredibly enough, this is not the only vision-related breakthrough scientists have achieved this week. In a separate study, doctors were able to actually reverse blindness in 12 babies born with congenital cataracts. By removing the damaged lens and “coaxing nearby cells to repair the damage,” surgeons were able to create an entirely novel way of treating one of the most common eye diseases in the world today.
“An ultimate goal of stem cell research is to turn on the regenerative potential of one’s own stem cells for tissue and organ repair and disease therapy,” said Dr. Kang Zhang of the UC San Diego School of Medicine, who helped develop the technology involved in the remarkable success. He added, “… this work represents a new approach in how new human tissue or organs can be regenerated and human disease can be treated, and may have a broad impact on regenerative therapies by harnessing the regenerative power of our own body.”
This innovation, combined with that of the Japanese team, could result in what Zhang calls a “paradigm shift,” changing the way we treat eye disease forever.
